MAGL is the principal enzyme responsible for the in vivo degradation of 2-arachidonoyl glycerol (2-AG), an endogenous ligand of the cannabinoid receptors (e.g., CB1 and CB2). See e.g., Patel, J. Z. et al., “Loratadine analogues as MAGL inhibitors,” Bioorg. Med. Chem. Lett., 2015, 25(7):1436-42; Mechoulam, R. et al., “Identification of an endogenous 2-monoglyceride, present in canine gut, that binds to cannabinoid receptors” Biochem. Pharmacol., 50 (1995), 83-90; Sugiura, T. et al., “2-Arachidonoylglycerol: a possible endogenous cannabinoid receptor ligand in brain,” Biochem. Biophys. Res. Commun., 215 (1995), 89-97.
MAGL inhibitors are potentially useful for the treatment of a MAGL-mediated disease or disorder. Examples of MAGL-mediated diseases or disorders include a metabolic disorder (e.g., obesity); vomiting or emesis; nausea; an eating disorder (e.g., anorexia or bulimia); neuropathy (e.g., diabetic neuropathy, pellagric neuropathy, alcoholic neuropathy, Beriberi neuropathy); burning feet syndrome; a neurodegenerative disorder [multiple sclerosis (MS), Parkinson's disease (PD), Huntington's disease, Alzheimer's disease, amyotrophic lateral sclerosis (ALS), epilepsy, a sleep disorder, Creutzfeldt-Jakob disease (CJD), or prion disease]; a cardiovascular disease (e.g., hypertension, dyslipidemia, atherosclerosis, cardiac arrhythmias, or cardiac ischemia); osteoporosis; osteoarthritis; schizophrenia; depression; bipolar disease; tremor; dyskinesia; dystonia; spasticity; Tourette's syndrome; sleep apnea; hearing loss; an eye disease (e.g., glaucoma, ocular hypertension, macular degeneration, or a disease arising from elevated intraocular pressure); cachexia; insomnia; meningitis; sleeping sickness; progressive multifocal leukoencephalopathy; De Vivo disease; cerebral edema; cerebral palsy; withdrawal syndrome [alcohol withdrawal syndrome, antidepressant discontinuation syndrome, antipsychotic withdrawal syndrome, benzodiazepine withdrawal syndrome, Cannabis withdrawal, neonatal withdrawal, nicotine withdrawal, or opioid withdrawal]; traumatic brain injury; spinal cord injury; seizures; excitotoxin exposure; ischemia [stroke, hepatic ischemia or reperfusion, CNS ischemia or reperfusion]; liver fibrosis, iron overload, cirrhosis of the liver; a lung disorder [asthma, allergies, COPD, chronic bronchitis, emphysema, cystic fibrosis, pneumonia, tuberculosis, pulmonary edema, lung cancers, acute respiratory distress syndrome, intersitital lung disease (ILD), sarcoidosis, idiopathic pulmonary fibrosis, pulmonary embolism, pleural effusion, or mesothelioma]; a liver disorder [acute liver failure, Alagille syndrome, hepatitis, enlarged liver, Gilbert's syndrome, liver cysts, liver hemangioma, fatty liver disease, steatohepatitis, primary sclerosing cholangitis, fascioliasis, primary bilary cirrhosis, Budd-Chiari syndrome, hemochromatosis, Wilson's disease, or transthyretin-related hereditary amyloidosis], stroke [e.g., ischemic stroke; hemorrhagic stroke]; subarachnoid hemorrhage; vasospasm; AIDS wasting syndrome; renal ischemia; a disorder associated with abnormal cell growth or proliferation [e.g., a benign tumor or cancer such as benign skin tumor, brain tumor, papilloma, prostate tumor, cerebral tumor (glioblastoma, medulloepithelioma, medulloblastoma, neuroblastoma, astrocytoma, astroblastoma, ependymoma, oligodendroglioma, plexus tumor, neuroepithelioma, epiphyseal tumor, ependymoblastoma, malignant meningioma, sarcomatosis, melanoma, schwannoma), melanoma, metastatic tumor, kidney cancer, bladder cancer, brain cancer, glioblastoma (GBM), gastrointestinal cancer, leukemia or blood cancer]; an autoimmune disease [e.g., psoriasis, lupus erythematosus, Sjögren's syndrome, ankylosing spondylitis, undifferentiated spondylitis, Behcet's disease, hemolytic anemia, graft rejection]; an inflammatory disorder [e.g., appendicitis, bursitis, colitis, cystitis, dermatitis, phlebitis, rhinitis, tendonitis, tonsillitis, vasculitis, acne vulgaris, chronic prostatitis, glomerulonephritis, hypersensitivities, IBS, pelvic inflammatory disease, sarcoidosis, HIV encephalitis, rabies, brain abscess, neuroinflammation, inflammation in the central nervous system (CNS)]; a disorder of the immune system (e.g., transplant rejection or celiac disease); post-traumatic stress disorder (PTSD); acute stress disorder; panic disorder; substance-induced anxiety; obsessive-compulsive disorder (OCD); agoraphobia; specific phobia; social phobia; anxiety disorder; attention deficit disorder (ADD); attention deficit hyperactivity disorder (ADHD); Asperger's syndrome; pain [e.g., acute pain; chronic pain; inflammatory pain; visceral pain; post-operative pain; migraine; lower back pain; joint pain; abdominal pain; chest pain; postmastectomy pain syndrome; menstrual pain; endometriosis pain; pain due to physical trauma; headache; sinus headache; tension headache arachnoiditis, herpes virus pain, diabetic pain; pain due to a disorder selected from: osteoarthritis, rheumatoid arthritis, osteoarthritis, spondylitis, gout, labor, musculoskeletal disease, skin disease, toothache, pyresis, burn, sunburn, snake bite, venomous snake bite, spider bite, insect sting, neurogenic bladder, interstitial cystitis, urinary tract infection (UTI), rhinitis, contact dermatitis/hypersensitivity, itch, eczema, pharyngitis, mucositis, enteritis, irritable bowel syndrome (IBS), cholecystitis, and pancreatitis; neuropathic pain (e.g., neuropathic low back pain, complex regional pain syndrome, post trigeminal neuralgia, causalgia, toxic neuropathy, reflex sympathetic dystrophy, diabetic neuropathy, chronic neuropathy from chemotherapeutic agent, or sciatica pain)]; a demyelinating disease [e.g., multiple sclerosis (MS), Devic's disease, CNS neuropathies, central pontine myelinolysis, syphilitic myelopathy, leukoencephalopathies, leukodystrophies, Guillain-Barre syndrome, chronic inflammatory demyelinating polyneuropathy, anti-myelin-associated glycoprotein (MAG) peripheral neuropathy, Charcot-Marie-Tooth disease, peripheral neuropathy, myelopathy, optic neuropathy, progressive inflammatory neuropathy, optic neuritis, transverse myelitis]; and cognitive impairment [e.g., cognitive impairment associated with Down's syndrome; cognitive impairment associated with Alzheimer's disease; cognitive impairment associated with PD; mild cognitive impairment (MCI), dementia, post-chemotherapy cognitive impairment (PCCI), postoperative cognitive dysfunction (POCD)]. See e.g., U.S. Pat. Nos. 8,415,341, 8,835,418, or U.S. Pat. No. 8,772,318.
There continues to be a need for alternative MAGL inhibitors.